1. Field of the Invention
The present invention relates to an image display device and a method for adjusting color thereof. More particularly, the present invention relates to an image display device capable of adjusting color as demanded by a user by updating real time a look-up table.
2. Description of the Related Art
As digital electronic engineering develops, conventional analog data has been replaced by digital data and accordingly, technologies for processing versatile digital image data have been introduced in order for effective processing of a great amount of data.
Standardization has appeared according to introduction of such versatile digital image processing technologies. Through the standardization, the digital image processing technologies can be widely in computer and communication industries, including applications such as a video conference system, a digital broadcasting codec system and a picture phone technology.
For example, a digital image compression technology, which is to store information onto an optical disc such as compact disc-read only memory (CD-ROM) or other digital storage medium, has the nearly same basis as a compression technology for visible communication.
Image signals according to the conventional art are processed in a three-dimension color space represented by red (R), green (G) and blue (B) and displayed through light sources of the three colors. Since R, G and B are the three primary colors constituting all colors, the image signals can be expressed using color signals of the three colors.
Most of recently-introduced image displaying devices have capability of expressing respective colors differently from input color signals. Even in one device, colors may be reproduced a little bit differently.
FIG. 1 shows color coordinates suggested by a high-definition television (HDTV) and color coordinates representable through an image displaying device.
Referring to FIG. 1, the color coordinates (RGB) A suggested by a high definition television (HDTV) standard, color coordinates B of a currently marketed liquid crystal display (LCD) TV, and color coordinates C of a digital lighting processing (DLP) have all different forms from one another.
In other words, a color space (a space corresponding to the color coordinates suggested by the HDTV standard) of signals input to the image displaying device and a color space (a space corresponding to the color coordinates of currently-marketed various TVs) representable by the image displaying device are different from each other.
In order to overcome such a problem that the input color signals are displayed on the image displaying device in different colors, various methods for compensating the color difference have been suggested. One of the methods uses a three-dimension look-up table (LUT) for more correct reproduction of colors.
The technique using the LUT realizes high accuracy but is difficult to update in real time. Therefore, the LUT is used only for color compensation while other techniques having relatively lower accuracy are utilized together with the LUT to adjust colors real time.
A converter which converts an LUT real time is disclosed in Japanese Patent Laid-open No. 2000-083176. In this converter, an already decided color compensation LUT for converting colors and at least one LUT preset by a user are integrated. However, conversion of the LUT is dependent upon the number of the already decided LUTs. In addition, the above converter requires a dedicated memory for storing the LUTs.
As a result, a method capable of accurately adjusting the colors real time using only the LUT technique but not requiring a dedicated hardware structure.